A laser toner cartridge contains a few significant components that directly affect the print quality and durability over time. These significant components are all located in the development section of the cartridge. The above mentioned components are the photosensitive drum that is made of an electrically conducting material such as aluminum, the developing roller, the regulating member and the primary charge roller.
Referring to FIG. 1, as known in the art, a photosensitive drum assembly 20 also known in the art as Organic-Photo-Conductor (OPC) may include an aluminum cylinder, also known as drum-cylinder, 22 whose outer surface has been treated with anodizing and a photosensitive coating (not shown), a helical gear assembly 24 with helical teeth 26, and a helical drive gear assembly 28 with helical teeth 30.
As known in the art, during operation of a laser printer cartridge, the photosensitive drum assembly 20 rotates as its drive gear assembly 28 is rotated. Specific models of laser cartridges are known to have specific gear designs for the drive gear assembly 28. The drive gear assembly 28 is typically attached to the aluminum cylinder 22 by mechanical crimping and coupling process, such as, for example, described in U.S. Pat. No. 7,248,814. After some testing, it has been determined that an application of about 5 ft. lbs. of torque to the drive gear assembly 28 could cause the mechanical crimping and coupling process to fail and cause the photosensitive drum assembly 20 to separate from the drive gear assembly 28.
As a result of constant friction between the photosensitive drum assembly 20 and the primary charge roller (not shown), as well as friction between the developing roller (not shown), the printed media (not shown), and the cleaning member/wiper blade (not shown), the photo-conductive coating (not shown) on the aluminum cylinder 22 typically wears off and/or degrades as the laser cartridge is depleted. This wearing off and/or degradation of the coating (not shown) on the aluminum cylinder 22 may in turn reduce print quality of the laser cartridge when it is remanufactured. The amount of wear and/or degradation of the coating depends on multiple factors such as, for example: type of media printed, average coverage area of the printed documents, type of toner used, type of documents printed (short: 1-2 pages or long: 100+ pages), and/or type of coating etc. To improve print quality in the remanufactured cartridges, the aluminum cylinder 22 is typically treated as an exhausted component and is replaced by a new one during the remanufacturing processes.
While the aluminum cylinder 22 may become exhausted during a single lifecycle of the laser cartridge, the photosensitive drum assembly 20's drive gear assembly 28 typically does not degrade and/or wear out with such use, and may be re-used. In order to reduce costs of remanufacturing a laser toner cartridge and to improve print quality of the remanufactured laser cartridges, and to reduce waste a need exists for a process and associated apparatus by which the aluminum cylinder 22 with worn out/degraded coating is replaced and the drive gear assembly 28 from the original laser toner cartridge is reused.
In the following description, like reference numbers are used to identify like elements. Furthermore, the drawings are intended to illustrate major features of exemplary embodiments in a diagrammatic manner. The drawings are not intended to depict every feature of every implementation nor relative dimensions of the depicted elements, and are not drawn to scale.